With the computer set for Extended Desktop mode (see October 1 post), next is to setup PowerPoint to make use of the second monitor.
In PowerPoint go to: SLIDE SHOW >> SETUP SHOW
In the Multiple Monitors section click the drop down menu and select “Monitor 2 Default Monitor.”
Now the slide show will be on the second monitor (usually a projector) and your monitor will remain in Slide Design Mode.
– Troy @ TLC